1. Field of the Invention
The present invention relates to a device for the invasive thermometrical measurement and the introduction of a medicament for surface and deep hyperthermia treatments.
More specifically, the invention relates to a device which allows one to obtain with the maximum precision, the temperature reached employing the hyperthermia techniques in the zone to be treated, in order to optimize the therapeutic effect and if desired to introduce medicaments within the tissue.
2. Description of Prior Art
It is well known that hyperthermia is a therapy-active technology employed in the last ten years in the treatment of the cancer.
During the application of the hyperthermia therapy, radio-frequency and/or microwave apparatuses deposit electromagnetic waves within the organism thus producing heat within the organism, and it is necessary to take a measurement of the temperature within the treated zone in order to obtain the maximum result.
In order to obtain the maximum effect on the tumoral cells the temperature within the tumor reaches a temperature of approximately 42.5.degree.-43.degree. C., with a margin of error of +/-0.1.degree. C.
It clearly follows that to obtain good results for the therapy, the temperature measurement systems must be able to operate with some precision.
After many years of experimentation, although the technology to deposit heat in depth has been improved, the invasive thermometric systems presently available have not reached a technological level similar to that of the apparatuses for the application of the hyperthermia, which still have remarkable drawbacks and contraindications.
In fact, the thermometric systems presently available are made up of constatan copper thermocouples and/or optical fiber introduced within the tumor by the introduction of needles-cannulae width 14-18 mm (+/-1.5 mm) and length 3-7.5 cm. The needles-cannulae are then drawn out leaving the wire bearing the thermocouple within the tissue.
With this technology, for each needle-cannula an average of one or two thermocouples and/or optical fibers are introduced. For each therapy treatment it is necessary to take 8-15 temperature reading points and therefore, it is necessary to employ from 4 to 15 needles.
This operation must be repeated for each hyperthermia treatment, for the complete cycle (5-10 treatments). Obviously it creates many inconveniences both for the patients, who must be pierced each time with needles of relatively large sizes, and for the operators who have practical and technical problems in correctly positioning and maintaining the thermocouple in the reading point.
In fact, for example, when drawing out the needle, very often the position of the thermocouple changes within the tissue thus having a negative effect on the temperature efficiency.
Although it facilitates the keeping of the position of the thermocouple within the tumoral zone, the presence of the needle within the organism is not allowed since it causes very strong pains for the patient both in case of muscle twitch and for the overheating of the needle (70.degree.-80.degree. C.) subjected to radiofrequency, RF.
Summarizing, the drawbacks of the present invasive thermometrical measurement systems can be individuated in a high needle/thermocouple number for each treatment, a needle cross-section that causes strong pains to the patients, a lack of precision of the positioning and maintaining the thermocouple at the correct reading point, the impossibility of maintaining the needle within the organism due to the overheating due to the radiofrequency, a scarce utilization practicality, a difficult possibility of use, and an inconvenience for the use in hyperthermia therapy in the medical field.
During the years, temperature reading systems of the non invasive kind have been suggested employing the TAC, the magnetic resonance and the radiometry.
However, the invasive reading of the temperature is until now the most precise and correct way.
In "International Journal of Hyperthermia", Vol. 2 No. 1 Jan-March 1986, a device is described having many of the disadvantages listed above.